Fastening device



Nov. 4, 1952 w. LQBUSH ET AL 2,616,642

FASTENING DEVICE Filed July 8, 1948 M "zlkzp L- BUS]? Juspph F. VpamhPatented Nov. 4, 1952 FASTENING DEVICE Wilkie L. Bush and Joseph G.Veatch, Elkhart, Ind., assignors to Chicago Telephone SupplyCorporation, Elkhart, Ind., a corporation of Indiana Application July 8,1948, Serial No. 37,554

Claims.

This invention relates to fastening devices and has particular referenceto fastening devices of the type used for the attachment of electricalcontrol instruments such as volume and tone controls for radio receiversto supporting panels on the receivers.

In the past it has been suggested that such control instruments besecured onto one side of a panel by means of tangs projecting from theinstruments through slit-like apertures in the panel, with the tangseither twisted or folded over the opposite side of the panel to securethe instruments in place. Examples of this type of mounting forelectrical control instruments are Patent No. 2,059,813 issued November3, 1936, to Newton C. Schellenger, and Patent No. 2,352,454 issued June2'7, 1944, to Newton C. Schellenger and Wilbert H. Budd.

One of the main objections to attaching electrical control instrumentsto their supporting panels in this manner, however, is that there islittle assurance that the tangs will have sufficient strength to resistbending due to rough handling either during assembly of the radioreceiver at the factory or during use of the radio in the home.Obviously, if the attaching tangs stretch or bend, the controlinstruments become loosened on their panels in a highly objectionablemanher which reflects upon the quality of workmanship in the radioreceiver.

Moreover, since the housing of control instruments of the characterdescribed must have positive electrical contact with the panels to whichthey are connected so as to effect electrical grounding of the housingfor shielding purposes, it is highly important that the controlinstruments be securely fastened to their panels against loosening toguard against breaking of such ground connections. However, because ofthe necessity of maintaining a secure grounding connection between thecontrol instrument and its panel, most manufacturers entirely avoid theuse of fastening tangs, and instead provide their instruments withthreaded mounting bushings surrounding the operating shaft of theinstrument to enable the panel to be positively clamped between theinstrument and a nut threaded on the bushing.

In recognition of the shortcomings of tang fasteners as suggested in thepast, it is an object of the present invention to provide an improvedfastening device for electrical control instruments such as tone andvolume controls for small radios whichwill at all times securely holdthe instrument against its supporting panel and which will precludeloosening of the instrument even though it may be subjected to roughhandling during assembly of the radio receiver or during use of thereceiver in the home.

More specifically it is an object of this invention to provide a controlinstrument of the character described with tangs projectable throughholes in the supporting panel upon which the instrument is to bemounted, and to provide for securement of the instrument to the panel bymeans of a single spring retaining loop common to all of the tangs ortabs and snapped into place between inclined cam surfaces on theextremities of the tabs and the panel to firmly draw the part againstthe panel and hold the same against motion relative thereto.

With the above and other objects in view, which will appear as thedescription proceeds this invention resides in the novel construction,combination and arrangement of parts substantially as hereinafterdescribed and more particularly defined by the appended claims, it beingunderstood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

The accompanying drawing illustrates two complete examples of thephysical embodiment of the invention constructed according to the bestmodes so far devised for the practical application of the principlesthereof, and in which:

Figure 1 is a perspective view of an electrical control device providedwith the fastening means of this invention but showing the deviceseparated from its supporting panel.

Figure 2 is an elevational view showing the control device attached tothe panel and illustrating the cooperation between the single springretaining element and the tabs which project through the panel from thecontrol device;

Figure 3 is an enlarged fragmentary sectional view taken along the planeof the line 3-3 of Figure 2;

Figure 4 is a view similar to Figure 2 showing a slightly modifiedembodiment of the invention;

Figure 5 is an enlarged fragmentary sectional view taken through Figure4 along the plane of the line 55; and

Figure 6 is a perspective view showing the construction and arrangementof the tabs for the fastening device of Figure 4.

Referring now more particularly to the accompanying drawing in whichlike numerals indicate like parts, the numeral 5 generally designates anelectrical control instrument which may be assumed to be a tone orvolume control for small radio receivers. The device includes asubstantially cup-shaped metallic housing 6 having a cylindrical sidewall, and the open end of the housing is closed by an insulatingterminal plate 'I having a central aperture through which the operatingshaft 8 of the device projects. A plurality of tangs 9 formed asextensions of the side wall of the housing are struck over the outerface of the terminal plate to hold the same in position closing thehousing.

The instrument is adapted to be mounted upon one side of the panel ill,usually at its back, of a small radio receiver (not shown), and for thispurpose the panel is provided with an aperture II to receive theoperating shaft 8 of the instrument.

According to this invention, the control instrument 5 is provided with anumber of attaching tangs or tabs I2 formed integral with the side wallof the housing 6 as continuations thereof. These tabs are projectablethrough holes I3 in the panel, and have neck portions I4 which projectstraight back from the side wall of the housing 6, and feet I5 on theirouter extremities bent outwardly at an angle slightly more than 90 tothe neck portions I4 of the tabs.

When the instrument '5 is applied to the back of the supporting panel,the tabs I2 project through the holes I3 of the panel and the feet I5 onthe tabs are disposed at the opposite side, or front of the panel. Theholes I3 in the panel, of course, are large enough to enable theangularly disposed feet I5 to be readily passed therethrough. 7

Shoulders I6 on the neck portions I4 engage the back of the panel toposition the feet I5 at the front of the panel with their undersides'I'I spaced outwardly a slight distance from the front plane of thepanel, as shown best in Figure 3, so that the feet thus provideoverhanging ledges on the tabs all of which extend radially outwardlyfrom the axis of the control shaft-8.

Since the feet I5 are disposed at an angle slightly greater than 90 tothe neck portions I4 of the tabs, it will be noted that the undersidesof the feet facing the front plane of the panel provide cam surfaceswhich slope outwardly away from the panel toward the outer extremitiesof the feet. Although not essential, the taings are preferably locatedequidistant from one another along the side wall of the housing 6 withthe heck portions I4 of the tabs concentric to the axis of the operatingshaft 8. According to this invention the control instrument is adaptedto be retained in position upon the back of the supporting panel I bymeans of a single retaining device I8 engageable with all of the tabs onthe control instrument. The retaining device comprises asingle loop ofspring wire disposed flatwise against the front face of the panel underthe feet I of the tabs and contracted into engagement with the inclinedcam surfaces I! on the tabs under substantial spring force. Thecontractive force of the spring wire I8 acting on the'inclined camsurfaces I! in this manner tends to move the feet I5 outwardly of thesupporting panel I0, and firmly draws the shoulders on the tabsagainsttheback of the panel and thus securely holds the control device 5connected thereto.

Hence, itwillbenoted thatthespring wir'eloop I8 securely wedges itselfbetween the panel "and the feet I5 on the tabs to preclude separationofthe control instrument from the panel, while the engagement between theside edges of the 'tabs and the sides of theh'oles I2 in thep'anelpreclude rotation or lateral shifting of the con-trolinstruincline, andhence can have practically no cam ining effect upon the spring wire looptending to force the loop outwardly from beneath the feet even when adeliberate attempt is made to pull the instrument away from the panelIII.

In the embodiment of the invention illustrated in Figures 4, 5, and 6,the tabs I2 are formed as an integral part of a metallic cover plate 20flatwi's'e covering the outer face of the terminal plate I and held inposition thereagainst by means of thetangs 9 folded over from thecylindri'cal side wall of the housing 6. The cover plate 20 is a sheetmetal stamping, and has four tabs I2 bent up out of the plane of theplate to lie substantially at right angles thereto. These tabs are bentalong substantially radial bend lines 2| so that the tabs liesubstantially edgewise to the axis of the operating shaft 8 of thecontrol instrument.

The tabs I2 are not necessarily equispaced from one another but arenevertheless circumferentially spaced from each other and equidistantfrom the axis of the operating shaft. In this case also, the tabs havefeet I5 on their outer extremities projected forwardly through holes I3in the panel so that the feet lie at the front "of the panel. Inclinedcam surfaces H are likewise provided on the undersides of the feet I5but in the present instance the cam surfaces are formed by substantiallyV-shaped notches 23 out into the inner edges of the tabs so that the camsurfaces I I slope inwardly toward 'the plane of the adjacent face ofthe panel In from the inner edges of the tabs. The sides of the notchesopposite the inclined cam surfaces I'I' also provide shoulders 24 whichabut against the back of the panel to be drawn tightly thereagainst bythe expansive force of a spring wire loop I3 snapped into the notches 23and hence wedged between the inclined cam surfaces I1 and the front-ofthe panel.

In'this'oase also it'will be noted that while the force of the expansivesp'ring wire loop I8 assures against separation of the control devicefrom the supporting panel, the engagement of the opposite {side edges ofthe tabs I2 with the sides offthe holes I3 precludes rotation or lateralshifting of the control instrument relative t'o'flthe panel.

While it will be apparent that the fastening means of this invention mayemploy either an expansive or contractive spring wire loop it will also*be readily appreciated that the tabs I2 and I2 may have inclined camsurfaces thereon for'rned to make "use "of either type of "spring.

In the Figure 1"enibodiinentthis would merely entail bending of the feetI5 inwardly toward 'a point substantially centrally located between thetabs; and in the Figure 4 embodiment a contraet'able spring wire loopcould be employed if the notches 23 were formed in the outer side edgesof the tabs I2.

From the foregoing description taken in confn'ecti'on with theaccompanyingdrawing, it will be readily apparent to those skilled in theart that the fastening means of this invention 'provides anexceptionally simple but secure manner of mounting an electrical controlinstrument to its supporting panel without entailing twisting or bendingof the tab elements of the fastening --means'over the panel.

tabs on said instrument projecting therefrom through holes in the paneland grouped about a point located centrally between them and edgewisesubstantially radial to said point with their fiat sides lying in planessubstantially normal to the panel; a spring ring lying flat against thefront of the panel and coacting with the tabs to hold the instrument onthe panel; all of said tabs being on the same side (circumferentially)of the spring ring and having integral feet thereon lying in the planesof the tabs, said feet projecting laterally edgewise over the springring with their under edges in contact therewith and receding from theplane of the front of the panel toward the outer ends of the tabs sothat said under edges of the feet provide cam surfaces which hold thespring ring under tension, whereby the radial force engendered upon thecam surfaces by the spring ring is resolved into a force which draws theinstrument toward the back of the panel; and abutment means on theinstrument contiguous to said tabs and held tightly pressed against theback of the panel under the force of the spring ring acting through saidcam surfaces.

2. Means for anchoring an instrument upon the back of a panel from thefront thereof, comprising: a plurality of relatively flat spaced aparttabs on the instrument projecting therefrom through locating holes inthe panel to thereby hold said instrument against rotation and lateralshifting on the panel, said tabs bein grouped about and substantiallyequi-distant from a point located substantially centrally between them,and the tabs being arranged with their flat sides in planessubstantially radial to said point and normal to the panel, said tabshaving notches in one edge thereof and all of said notches extending inthe same radial direction with respect to said central point, one edgeof the notch of each tab providing a shoulder engaging the back of thepanel and the other edge of each notch providing an inclined cam surfacewhich is spaced from but converges toward the front of the panel and thebottom of the notch; and a spring ring lying fiatwise against the frontof the panel and engaged in said notches to exert a radial force uponsaid converging edges of the notches which force is resolved therebyinto a force which draws said shoulders on the tabs against the back ofthe panel and effects clamping of the panel between the shoulders andthe spring ring to thereby hold the instrument firmly in position on thepanel.

3. The anchoring means set forth in claim 2 .e

wherein said tabs are bent up from a metallic cover plate secured to theinstrument to lie between the instrument and the back of the panel.

4. As an article of manufacture, means providing for attachment of aninstrument on the back of a panel from the front thereof, comprising: ametallic cover plate securable to an instrument to be mounted upon thepanel; a number of relatively flat spaced apart tabs integral with thecover plate and bent up to one side thereof with their flat sidessubstantially normal to the plane of the plate and substan tially radialto a point located substantially centrally between the tabs and fromwhich the tabs are substantially equi-spaced, said tabs having notchesin one edge thereof all extending into the tabs in the same radialdirection with respect to said central point, the edges of said notcheswhich are adjacent to the plate lying in a common plane substantiallyparallel to the plate, and said tabs being wider at their base portionsadjoining the plate so that said sub stantially coplanar edges of thenotches provide shoulders adapted to engage the back of a panel uponwhich the instrument is to be mounted, and the other edges of saidnotches converging toward the bottoms of the notches so as to provideinclined cam surfaces which are adapted to be disposed at the front of apanel upon which the instrument is to be mounted when the tabs areinserted through apertures in the panel and held spaced a uniformdistance from the front of the panel by said shoulders, so that a springring snapped into said notches between their converging edges and thefront of the panel may exert a radial force upon said cam surfaces,which radial force will be resolved by the cam surfaces into a force onthe tabs normal to the cover plate by which said shoulders on the tabsare drawn firmly against the back of the panel upon which the instrumentis to be mounted.

Attaching means for mounting an instrument upon the back of a panel fromthe front thereof, comprising: a metallic cover plate securable to theinstrument and having a number of relatively flat spaced apart tabs benttherefrom and arranged with their flat sides in planes normal to theplate and substantially radial to a central point about which the tabsare grouped and from which the tabs are substantially equidistant, saidtabs being wider at their base portions adjoining the plate than attheir outer end portions, and having notches in one edge thereof allextending in the same direction with respect to said central point, oneedge of each notch being on the wider portion of the tab and said edgeslying in substantially a common plane normal to the planes of the sidesof the tabs, and the other edges of the notches being convergent to thefirst designated edges toward the bottoms of the notches; and a springring engaged in said. notches and biased toward the bottoms thereof toreact between said convergent edges thereof and the front of a panelhaving holes through which the tabs may project from its rear, and byits radial force and its engagement with the converging edges of thenotches draw the shoulder defining edges of the notches against the backof the panel and thus firmly clamp an instrument to which the coverplate is attached onto the back of the panel.

WILKIE L. BUSH. JOSEPH G. VEATCI-I.

REFERENCES QITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

